###### (This is the documentation for SDL3, which is the current stable version. [SDL2](https://wiki.libsdl.org/SDL2/) was the previous version!) # SDL_InitState A structure used for thread-safe initialization and shutdown. ## Header File Defined in [](https://github.com/libsdl-org/SDL/blob/main/include/SDL3/SDL_mutex.h) ## Syntax ```c typedef struct SDL_InitState { SDL_AtomicInt status; SDL_ThreadID thread; void *reserved; } SDL_InitState; ``` ## Remarks Here is an example of using this: ```c static SDL_AtomicInitState init; bool InitSystem(void) { if (!SDL_ShouldInit(&init)) { // The system is initialized return true; } // At this point, you should not leave this function without calling SDL_SetInitialized() bool initialized = DoInitTasks(); SDL_SetInitialized(&init, initialized); return initialized; } bool UseSubsystem(void) { if (SDL_ShouldInit(&init)) { // Error, the subsystem isn't initialized SDL_SetInitialized(&init, false); return false; } // Do work using the initialized subsystem return true; } void QuitSystem(void) { if (!SDL_ShouldQuit(&init)) { // The system is not initialized return true; } // At this point, you should not leave this function without calling SDL_SetInitialized() DoQuitTasks(); SDL_SetInitialized(&init, false); } ``` Note that this doesn't protect any resources created during initialization, or guarantee that nobody is using those resources during cleanup. You should use other mechanisms to protect those, if that's a concern for your code. ## Version This struct is available since SDL 3.1.3. ---- [CategoryAPI](CategoryAPI), [CategoryAPIStruct](CategoryAPIStruct), [CategoryMutex](CategoryMutex)